The present invention generally relates to a hook raising apparatus and more particularly, to an apparatus for raising hooks of semi-finished spring products which are produced by a spring manufacturing machine.
Conventionally, there have been various disadvantages as follows in the apparatuses of the above described type.
In the first place, since the known apparatus as referred to above is so arranged that semi-finished springs processed by a spring manufacturing machine are each transferred to a hook raising section by subjecting a horizontal rocking arm having a pair of vertically arranged upper and lower semi-finished spring holding pieces, to a rocking or pivotal movement in a horizontal direction, it has been extremely difficult to correctly discharge the springs completed for raising hooks and held between the holding pieces, only by the mere opening or spacing between the pair of upper and lower holding pieces, and therefore, in order to automatically discharge the processed springs from between said pair of upper and lower holding pieces, a spring discharge unit is required to be separately installed for the purpose. In the second place, in the conventional apparatus as described above, owing to the fact that no mechanism is provided for controlling position of the semi-finished spring held between the pair of upper and lower holding pieces, there have been cases where the semi-finished spring is not correctly positioned as preliminarily set with respect to hook raising tools, thus resulting in an increased rate of faulty items produced. In the third place, since the prior art apparatuses are generally arranged to effect the raising of hooks merely by holding the semi-finished springs between the pair of upper and lower holding pieces, there has been such an inconvenience that the pair of upper and lower holding pieces are undesirably spaced by yielding to a force which may be exerted on the semi-finished spring during the processing thereof.